Although RFID technology is used almost everywhere, its purchase, implementation and access of use are unfortunately limited to buyers of entire, proprietary systems and their permitted users. Organisations which would implement an RFID system are those which have a large number of physical objects to monitor, such as warehouses, libraries, departmental stores and so on. An RFID system implemented in these premises cannot be used by any casual member of the public to locate RFID tagged objects because the member of the public will need a suitable RFID detector and will also need to be given a database to identify objects which are detected by RFID. This causes great inconvenience at a huge cost to the management of these premises because manpower would have to be deployed to help the member of the public to locate tagged objects.
Use of handheld mobile communication devices such as mobile telephones has grown exponentially at the same time as use of RFID systems has. However, the growths of these two sectors are in fact independent and unrelated. Despite the mature state of these two markets and technologies, mobile telephones simply do not come pre-installed with RFID detectors. In the same way, RFID systems are not typically designed to allow any member of the public to use his mobile telephone as an RFID detector.
The mutual independence between these two technologies may be due to several constraints, one of which is the size of an antenna required for sufficiently strong RFID signal transmission and reception at reasonable distance. A handheld mobile communication device tend have a size suitable for being contained in a trouser pocket or to fit into the palm of a user. Therefore, such a device has insufficient space to allow for installation of a relatively bulky but effective RFID antenna. A small antenna cannot be used because the small size causes poor signal isolation and is frequently subject to signal jamming, and is also subjected to undesirable antenna impedance variation due to the ‘body effect’ of the user. The body effect is when an object in proximity to the antenna creates a sufficiently large change in antenna impedance affecting the efficiency of the antenna in receiving signals.
It is therefore desirable to propose devices and methods which possibly mitigate the constraints of implementing RFID antennae in such handheld mobile communication devices.